Tom Lewis moved into a share of the lead in the final round of the Portugal Masters as he and Lucas Herbert extended their advantage over the rest of the field at Dom Pedro Victoria Golf Course.
Australian Herbert entered the day with a two-shot lead over Lewis and while he played his first three holes in level par, Lewis made two birdies to join him at 19 under.
Swede Marcus Kinhult, China's Li Haotong and England's Eddie Pepperell were then at 16 under, a shot clear of Oliver Fisher and Mikko Korhonen.
Lewis won this event in 2011 in just his third start as a professional and has birdied 20 of his last 39 holes after opening with a 72 on Thursday.
Herbert is searching for his first professional win and also aiming to secure his full European Tour playing privileges for 2019 after playing this season on invites.
Pepperell hit the pin as he spun his approach into the second to set up a birdie and he was joined at 16 under by Kinhult who holed a four-footer at the first.
Lewis holed a long putt at the second for a birdie of his own to get within one and when playing partner Herbert bogeyed the same hole, the lead was shared.
Li had birdied the second and third and when he made it a hat-trick from three feet on the fourth, he joined Pepperell and Kinhult two off the lead.
Lewis holed a six-footer on the third to extend that gap to three but Herbert's approach was inside him and he also made a birdie to stay in a share.
England's Fisher - who carded the first 59 in European Tour history on Friday - was one under after four holes, with Finn Korhonen one under after three.
2012 champion Shane Lowry, Welshman Bradley Dredge and France's Raphaël Jacquelin were 14 under.
